gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2
   3    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   5    Free Software Foundation, Inc.
   6
   7    Contributed by Cygnus Support.  Written by John Gilmore.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #if !defined (TARGET_H)
  25 #define TARGET_H
  26
  27 struct objfile;
  28 struct ui_file;
  29 struct mem_attrib;
  30 struct target_ops;
  31 struct bp_target_info;
  32 struct regcache;
  33 struct target_section_table;
  34
  35 /* This include file defines the interface between the main part
  36    of the debugger, and the part which is target-specific, or
  37    specific to the communications interface between us and the
  38    target.
  39
  40    A TARGET is an interface between the debugger and a particular
  41    kind of file or process.  Targets can be STACKED in STRATA,
  42    so that more than one target can potentially respond to a request.
  43    In particular, memory accesses will walk down the stack of targets
  44    until they find a target that is interested in handling that particular
  45    address.  STRATA are artificial boundaries on the stack, within
  46    which particular kinds of targets live.  Strata exist so that
  47    people don't get confused by pushing e.g. a process target and then
  48    a file target, and wondering why they can't see the current values
  49    of variables any more (the file target is handling them and they
  50    never get to the process target).  So when you push a file target,
  51    it goes into the file stratum, which is always below the process
  52    stratum.  */
  53
  54 #include "bfd.h"
  55 #include "symtab.h"
  56 #include "dcache.h"
  57 #include "memattr.h"
  58 #include "vec.h"
  59 #include "gdb_signals.h"
  60
  61 enum strata
  62   {
  63     dummy_stratum,              /* The lowest of the low */
  64     file_stratum,               /* Executable files, etc */
  65     core_stratum,               /* Core dump files */
  66     process_stratum,            /* Executing processes */
  67     thread_stratum,             /* Executing threads */
  68     record_stratum              /* Support record debugging */
  69   };
  70
  71 enum thread_control_capabilities
  72   {
  73     tc_none = 0,                /* Default: can't control thread execution.  */
  74     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  75   };
  76
  77 /* Stuff for target_wait.  */
  78
  79 /* Generally, what has the program done?  */
  80 enum target_waitkind
  81   {
  82     /* The program has exited.  The exit status is in value.integer.  */
  83     TARGET_WAITKIND_EXITED,
  84
  85     /* The program has stopped with a signal.  Which signal is in
  86        value.sig.  */
  87     TARGET_WAITKIND_STOPPED,
  88
  89     /* The program has terminated with a signal.  Which signal is in
  90        value.sig.  */
  91     TARGET_WAITKIND_SIGNALLED,
  92
  93     /* The program is letting us know that it dynamically loaded something
  94        (e.g. it called load(2) on AIX).  */
  95     TARGET_WAITKIND_LOADED,
  96
  97     /* The program has forked.  A "related" process' PTID is in
  98        value.related_pid.  I.e., if the child forks, value.related_pid
  99        is the parent's ID.  */
 100
 101     TARGET_WAITKIND_FORKED,
 102
 103     /* The program has vforked.  A "related" process's PTID is in
 104        value.related_pid.  */
 105
 106     TARGET_WAITKIND_VFORKED,
 107
 108     /* The program has exec'ed a new executable file.  The new file's
 109        pathname is pointed to by value.execd_pathname.  */
 110
 111     TARGET_WAITKIND_EXECD,
 112
 113     /* The program has entered or returned from a system call.  On
 114        HP-UX, this is used in the hardware watchpoint implementation.
 115        The syscall's unique integer ID number is in value.syscall_id */
 116
 117     TARGET_WAITKIND_SYSCALL_ENTRY,
 118     TARGET_WAITKIND_SYSCALL_RETURN,
 119
 120     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 121        within target_wait, but I'm not sure target_wait should be resuming the
 122        inferior.  */
 123     TARGET_WAITKIND_SPURIOUS,
 124
 125     /* An event has occured, but we should wait again.
 126        Remote_async_wait() returns this when there is an event
 127        on the inferior, but the rest of the world is not interested in
 128        it. The inferior has not stopped, but has just sent some output
 129        to the console, for instance. In this case, we want to go back
 130        to the event loop and wait there for another event from the
 131        inferior, rather than being stuck in the remote_async_wait()
 132        function. This way the event loop is responsive to other events,
 133        like for instance the user typing.  */
 134     TARGET_WAITKIND_IGNORE,
 135
 136     /* The target has run out of history information,
 137        and cannot run backward any further.  */
 138     TARGET_WAITKIND_NO_HISTORY
 139   };
 140
 141 struct target_waitstatus
 142   {
 143     enum target_waitkind kind;
 144
 145     /* Forked child pid, execd pathname, exit status or signal number.  */
 146     union
 147       {
 148         int integer;
 149         enum target_signal sig;
 150         ptid_t related_pid;
 151         char *execd_pathname;
 152         int syscall_id;
 153       }
 154     value;
 155   };
 156
 157 /* Options that can be passed to target_wait.  */
 158
 159 /* Return immediately if there's no event already queued.  If this
 160    options is not requested, target_wait blocks waiting for an
 161    event.  */
 162 #define TARGET_WNOHANG 1
 163
 164 /* Return a pretty printed form of target_waitstatus.
 165    Space for the result is malloc'd, caller must free.  */
 166 extern char *target_waitstatus_to_string (const struct target_waitstatus *);
 167
 168 /* Possible types of events that the inferior handler will have to
 169    deal with.  */
 170 enum inferior_event_type
 171   {
 172     /* There is a request to quit the inferior, abandon it.  */
 173     INF_QUIT_REQ,
 174     /* Process a normal inferior event which will result in target_wait
 175        being called.  */
 176     INF_REG_EVENT,
 177     /* Deal with an error on the inferior.  */
 178     INF_ERROR,
 179     /* We are called because a timer went off.  */
 180     INF_TIMER,
 181     /* We are called to do stuff after the inferior stops.  */
 182     INF_EXEC_COMPLETE,
 183     /* We are called to do some stuff after the inferior stops, but we
 184        are expected to reenter the proceed() and
 185        handle_inferior_event() functions. This is used only in case of
 186        'step n' like commands.  */
 187     INF_EXEC_CONTINUE
 188   };
 189 \f
 190 /* Target objects which can be transfered using target_read,
 191    target_write, et cetera.  */
 192
 193 enum target_object
 194 {
 195   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 196   TARGET_OBJECT_AVR,
 197   /* SPU target specific transfer.  See "spu-tdep.c".  */
 198   TARGET_OBJECT_SPU,
 199   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 200   TARGET_OBJECT_MEMORY,
 201   /* Memory, avoiding GDB's data cache and trusting the executable.
 202      Target implementations of to_xfer_partial never need to handle
 203      this object, and most callers should not use it.  */
 204   TARGET_OBJECT_RAW_MEMORY,
 205   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 206   TARGET_OBJECT_UNWIND_TABLE,
 207   /* Transfer auxilliary vector.  */
 208   TARGET_OBJECT_AUXV,
 209   /* StackGhost cookie.  See "sparc-tdep.c".  */
 210   TARGET_OBJECT_WCOOKIE,
 211   /* Target memory map in XML format.  */
 212   TARGET_OBJECT_MEMORY_MAP,
 213   /* Flash memory.  This object can be used to write contents to
 214      a previously erased flash memory.  Using it without erasing
 215      flash can have unexpected results.  Addresses are physical
 216      address on target, and not relative to flash start.  */
 217   TARGET_OBJECT_FLASH,
 218   /* Available target-specific features, e.g. registers and coprocessors.
 219      See "target-descriptions.c".  ANNEX should never be empty.  */
 220   TARGET_OBJECT_AVAILABLE_FEATURES,
 221   /* Currently loaded libraries, in XML format.  */
 222   TARGET_OBJECT_LIBRARIES,
 223   /* Get OS specific data.  The ANNEX specifies the type (running
 224      processes, etc.).  */
 225   TARGET_OBJECT_OSDATA,
 226   /* Extra signal info.  Usually the contents of `siginfo_t' on unix
 227      platforms.  */
 228   TARGET_OBJECT_SIGNAL_INFO,
 229   /* Possible future objects: TARGET_OBJECT_FILE, ... */
 230 };
 231
 232 /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 233    OBJECT.  The OFFSET, for a seekable object, specifies the
 234    starting point.  The ANNEX can be used to provide additional
 235    data-specific information to the target.
 236
 237    Return the number of bytes actually transfered, or -1 if the
 238    transfer is not supported or otherwise fails.  Return of a positive
 239    value less than LEN indicates that no further transfer is possible.
 240    Unlike the raw to_xfer_partial interface, callers of these
 241    functions do not need to retry partial transfers.  */
 242
 243 extern LONGEST target_read (struct target_ops *ops,
 244                             enum target_object object,
 245                             const char *annex, gdb_byte *buf,
 246                             ULONGEST offset, LONGEST len);
 247
 248 extern LONGEST target_read_until_error (struct target_ops *ops,
 249                                         enum target_object object,
 250                                         const char *annex, gdb_byte *buf,
 251                                         ULONGEST offset, LONGEST len);
 252
 253 extern LONGEST target_write (struct target_ops *ops,
 254                              enum target_object object,
 255                              const char *annex, const gdb_byte *buf,
 256                              ULONGEST offset, LONGEST len);
 257
 258 /* Similar to target_write, except that it also calls PROGRESS with
 259    the number of bytes written and the opaque BATON after every
 260    successful partial write (and before the first write).  This is
 261    useful for progress reporting and user interaction while writing
 262    data.  To abort the transfer, the progress callback can throw an
 263    exception.  */
 264
 265 LONGEST target_write_with_progress (struct target_ops *ops,
 266                                     enum target_object object,
 267                                     const char *annex, const gdb_byte *buf,
 268                                     ULONGEST offset, LONGEST len,
 269                                     void (*progress) (ULONGEST, void *),
 270                                     void *baton);
 271
 272 /* Wrapper to perform a full read of unknown size.  OBJECT/ANNEX will
 273    be read using OPS.  The return value will be -1 if the transfer
 274    fails or is not supported; 0 if the object is empty; or the length
 275    of the object otherwise.  If a positive value is returned, a
 276    sufficiently large buffer will be allocated using xmalloc and
 277    returned in *BUF_P containing the contents of the object.
 278
 279    This method should be used for objects sufficiently small to store
 280    in a single xmalloc'd buffer, when no fixed bound on the object's
 281    size is known in advance.  Don't try to read TARGET_OBJECT_MEMORY
 282    through this function.  */
 283
 284 extern LONGEST target_read_alloc (struct target_ops *ops,
 285                                   enum target_object object,
 286                                   const char *annex, gdb_byte **buf_p);
 287
 288 /* Read OBJECT/ANNEX using OPS.  The result is NUL-terminated and
 289    returned as a string, allocated using xmalloc.  If an error occurs
 290    or the transfer is unsupported, NULL is returned.  Empty objects
 291    are returned as allocated but empty strings.  A warning is issued
 292    if the result contains any embedded NUL bytes.  */
 293
 294 extern char *target_read_stralloc (struct target_ops *ops,
 295                                    enum target_object object,
 296                                    const char *annex);
 297
 298 /* Wrappers to target read/write that perform memory transfers.  They
 299    throw an error if the memory transfer fails.
 300
 301    NOTE: cagney/2003-10-23: The naming schema is lifted from
 302    "frame.h".  The parameter order is lifted from get_frame_memory,
 303    which in turn lifted it from read_memory.  */
 304
 305 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 306                                gdb_byte *buf, LONGEST len);
 307 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 308                                             CORE_ADDR addr, int len,
 309                                             enum bfd_endian byte_order);
 310 \f
 311 struct thread_info;             /* fwd decl for parameter list below: */
 312
 313 struct target_ops
 314   {
 315     struct target_ops *beneath; /* To the target under this one.  */
 316     char *to_shortname;         /* Name this target type */
 317     char *to_longname;          /* Name for printing */
 318     char *to_doc;               /* Documentation.  Does not include trailing
 319                                    newline, and starts with a one-line descrip-
 320                                    tion (probably similar to to_longname).  */
 321     /* Per-target scratch pad.  */
 322     void *to_data;
 323     /* The open routine takes the rest of the parameters from the
 324        command, and (if successful) pushes a new target onto the
 325        stack.  Targets should supply this routine, if only to provide
 326        an error message.  */
 327     void (*to_open) (char *, int);
 328     /* Old targets with a static target vector provide "to_close".
 329        New re-entrant targets provide "to_xclose" and that is expected
 330        to xfree everything (including the "struct target_ops").  */
 331     void (*to_xclose) (struct target_ops *targ, int quitting);
 332     void (*to_close) (int);
 333     void (*to_attach) (struct target_ops *ops, char *, int);
 334     void (*to_post_attach) (int);
 335     void (*to_detach) (struct target_ops *ops, char *, int);
 336     void (*to_disconnect) (struct target_ops *, char *, int);
 337     void (*to_resume) (struct target_ops *, ptid_t, int, enum target_signal);
 338     ptid_t (*to_wait) (struct target_ops *,
 339                        ptid_t, struct target_waitstatus *, int);
 340     void (*to_fetch_registers) (struct target_ops *, struct regcache *, int);
 341     void (*to_store_registers) (struct target_ops *, struct regcache *, int);
 342     void (*to_prepare_to_store) (struct regcache *);
 343
 344     /* Transfer LEN bytes of memory between GDB address MYADDR and
 345        target address MEMADDR.  If WRITE, transfer them to the target, else
 346        transfer them from the target.  TARGET is the target from which we
 347        get this function.
 348
 349        Return value, N, is one of the following:
 350
 351        0 means that we can't handle this.  If errno has been set, it is the
 352        error which prevented us from doing it (FIXME: What about bfd_error?).
 353
 354        positive (call it N) means that we have transferred N bytes
 355        starting at MEMADDR.  We might be able to handle more bytes
 356        beyond this length, but no promises.
 357
 358        negative (call its absolute value N) means that we cannot
 359        transfer right at MEMADDR, but we could transfer at least
 360        something at MEMADDR + N.
 361
 362        NOTE: cagney/2004-10-01: This has been entirely superseeded by
 363        to_xfer_partial and inferior inheritance.  */
 364
 365     int (*deprecated_xfer_memory) (CORE_ADDR memaddr, gdb_byte *myaddr,
 366                                    int len, int write,
 367                                    struct mem_attrib *attrib,
 368                                    struct target_ops *target);
 369
 370     void (*to_files_info) (struct target_ops *);
 371     int (*to_insert_breakpoint) (struct gdbarch *, struct bp_target_info *);
 372     int (*to_remove_breakpoint) (struct gdbarch *, struct bp_target_info *);
 373     int (*to_can_use_hw_breakpoint) (int, int, int);
 374     int (*to_insert_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 375     int (*to_remove_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 376     int (*to_remove_watchpoint) (CORE_ADDR, int, int);
 377     int (*to_insert_watchpoint) (CORE_ADDR, int, int);
 378     int (*to_stopped_by_watchpoint) (void);
 379     int to_have_steppable_watchpoint;
 380     int to_have_continuable_watchpoint;
 381     int (*to_stopped_data_address) (struct target_ops *, CORE_ADDR *);
 382     int (*to_watchpoint_addr_within_range) (struct target_ops *,
 383                                             CORE_ADDR, CORE_ADDR, int);
 384     int (*to_region_ok_for_hw_watchpoint) (CORE_ADDR, int);
 385     void (*to_terminal_init) (void);
 386     void (*to_terminal_inferior) (void);
 387     void (*to_terminal_ours_for_output) (void);
 388     void (*to_terminal_ours) (void);
 389     void (*to_terminal_save_ours) (void);
 390     void (*to_terminal_info) (char *, int);
 391     void (*to_kill) (struct target_ops *);
 392     void (*to_load) (char *, int);
 393     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 394     void (*to_create_inferior) (struct target_ops *,
 395                                 char *, char *, char **, int);
 396     void (*to_post_startup_inferior) (ptid_t);
 397     void (*to_acknowledge_created_inferior) (int);
 398     void (*to_insert_fork_catchpoint) (int);
 399     int (*to_remove_fork_catchpoint) (int);
 400     void (*to_insert_vfork_catchpoint) (int);
 401     int (*to_remove_vfork_catchpoint) (int);
 402     int (*to_follow_fork) (struct target_ops *, int);
 403     void (*to_insert_exec_catchpoint) (int);
 404     int (*to_remove_exec_catchpoint) (int);
 405     int (*to_has_exited) (int, int, int *);
 406     void (*to_mourn_inferior) (struct target_ops *);
 407     int (*to_can_run) (void);
 408     void (*to_notice_signals) (ptid_t ptid);
 409     int (*to_thread_alive) (struct target_ops *, ptid_t ptid);
 410     void (*to_find_new_threads) (struct target_ops *);
 411     char *(*to_pid_to_str) (struct target_ops *, ptid_t);
 412     char *(*to_extra_thread_info) (struct thread_info *);
 413     void (*to_stop) (ptid_t);
 414     void (*to_rcmd) (char *command, struct ui_file *output);
 415     char *(*to_pid_to_exec_file) (int pid);
 416     void (*to_log_command) (const char *);
 417     struct target_section_table *(*to_get_section_table) (struct target_ops *);
 418     enum strata to_stratum;
 419     int (*to_has_all_memory) (struct target_ops *);
 420     int (*to_has_memory) (struct target_ops *);
 421     int (*to_has_stack) (struct target_ops *);
 422     int (*to_has_registers) (struct target_ops *);
 423     int (*to_has_execution) (struct target_ops *);
 424     int to_has_thread_control;  /* control thread execution */
 425     int to_attach_no_wait;
 426     /* ASYNC target controls */
 427     int (*to_can_async_p) (void);
 428     int (*to_is_async_p) (void);
 429     void (*to_async) (void (*) (enum inferior_event_type, void *), void *);
 430     int (*to_async_mask) (int);
 431     int (*to_supports_non_stop) (void);
 432     int (*to_find_memory_regions) (int (*) (CORE_ADDR,
 433                                             unsigned long,
 434                                             int, int, int,
 435                                             void *),
 436                                    void *);
 437     char * (*to_make_corefile_notes) (bfd *, int *);
 438
 439     /* Return the thread-local address at OFFSET in the
 440        thread-local storage for the thread PTID and the shared library
 441        or executable file given by OBJFILE.  If that block of
 442        thread-local storage hasn't been allocated yet, this function
 443        may return an error.  */
 444     CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
 445                                               ptid_t ptid,
 446                                               CORE_ADDR load_module_addr,
 447                                               CORE_ADDR offset);
 448
 449     /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 450        OBJECT.  The OFFSET, for a seekable object, specifies the
 451        starting point.  The ANNEX can be used to provide additional
 452        data-specific information to the target.
 453
 454        Return the number of bytes actually transfered, zero when no
 455        further transfer is possible, and -1 when the transfer is not
 456        supported.  Return of a positive value smaller than LEN does
 457        not indicate the end of the object, only the end of the
 458        transfer; higher level code should continue transferring if
 459        desired.  This is handled in target.c.
 460
 461        The interface does not support a "retry" mechanism.  Instead it
 462        assumes that at least one byte will be transfered on each
 463        successful call.
 464
 465        NOTE: cagney/2003-10-17: The current interface can lead to
 466        fragmented transfers.  Lower target levels should not implement
 467        hacks, such as enlarging the transfer, in an attempt to
 468        compensate for this.  Instead, the target stack should be
 469        extended so that it implements supply/collect methods and a
 470        look-aside object cache.  With that available, the lowest
 471        target can safely and freely "push" data up the stack.
 472
 473        See target_read and target_write for more information.  One,
 474        and only one, of readbuf or writebuf must be non-NULL.  */
 475
 476     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 477                                 enum target_object object, const char *annex,
 478                                 gdb_byte *readbuf, const gdb_byte *writebuf,
 479                                 ULONGEST offset, LONGEST len);
 480
 481     /* Returns the memory map for the target.  A return value of NULL
 482        means that no memory map is available.  If a memory address
 483        does not fall within any returned regions, it's assumed to be
 484        RAM.  The returned memory regions should not overlap.
 485
 486        The order of regions does not matter; target_memory_map will
 487        sort regions by starting address. For that reason, this
 488        function should not be called directly except via
 489        target_memory_map.
 490
 491        This method should not cache data; if the memory map could
 492        change unexpectedly, it should be invalidated, and higher
 493        layers will re-fetch it.  */
 494     VEC(mem_region_s) *(*to_memory_map) (struct target_ops *);
 495
 496     /* Erases the region of flash memory starting at ADDRESS, of
 497        length LENGTH.
 498
 499        Precondition: both ADDRESS and ADDRESS+LENGTH should be aligned
 500        on flash block boundaries, as reported by 'to_memory_map'.  */
 501     void (*to_flash_erase) (struct target_ops *,
 502                            ULONGEST address, LONGEST length);
 503
 504     /* Finishes a flash memory write sequence.  After this operation
 505        all flash memory should be available for writing and the result
 506        of reading from areas written by 'to_flash_write' should be
 507        equal to what was written.  */
 508     void (*to_flash_done) (struct target_ops *);
 509
 510     /* Describe the architecture-specific features of this target.
 511        Returns the description found, or NULL if no description
 512        was available.  */
 513     const struct target_desc *(*to_read_description) (struct target_ops *ops);
 514
 515     /* Build the PTID of the thread on which a given task is running,
 516        based on LWP and THREAD.  These values are extracted from the
 517        task Private_Data section of the Ada Task Control Block, and
 518        their interpretation depends on the target.  */
 519     ptid_t (*to_get_ada_task_ptid) (long lwp, long thread);
 520
 521     /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
 522        Return 0 if *READPTR is already at the end of the buffer.
 523        Return -1 if there is insufficient buffer for a whole entry.
 524        Return 1 if an entry was read into *TYPEP and *VALP.  */
 525     int (*to_auxv_parse) (struct target_ops *ops, gdb_byte **readptr,
 526                          gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 527
 528     /* Search SEARCH_SPACE_LEN bytes beginning at START_ADDR for the
 529        sequence of bytes in PATTERN with length PATTERN_LEN.
 530
 531        The result is 1 if found, 0 if not found, and -1 if there was an error
 532        requiring halting of the search (e.g. memory read error).
 533        If the pattern is found the address is recorded in FOUND_ADDRP.  */
 534     int (*to_search_memory) (struct target_ops *ops,
 535                              CORE_ADDR start_addr, ULONGEST search_space_len,
 536                              const gdb_byte *pattern, ULONGEST pattern_len,
 537                              CORE_ADDR *found_addrp);
 538
 539     /* Can target execute in reverse?  */
 540     int (*to_can_execute_reverse) (void);
 541
 542     /* Does this target support debugging multiple processes
 543        simultaneously?  */
 544     int (*to_supports_multi_process) (void);
 545
 546     /* Determine current architecture of thread PTID.
 547
 548        The target is supposed to determine the architecture of the code where
 549        the target is currently stopped at (on Cell, if a target is in spu_run,
 550        to_thread_architecture would return SPU, otherwise PPC32 or PPC64).
 551        This is architecture used to perform decr_pc_after_break adjustment,
 552        and also determines the frame architecture of the innermost frame.
 553        ptrace operations need to operate according to target_gdbarch.
 554
 555        The default implementation always returns target_gdbarch.  */
 556     struct gdbarch *(*to_thread_architecture) (struct target_ops *, ptid_t);
 557
 558     int to_magic;
 559     /* Need sub-structure for target machine related rather than comm related?
 560      */
 561   };
 562
 563 /* Magic number for checking ops size.  If a struct doesn't end with this
 564    number, somebody changed the declaration but didn't change all the
 565    places that initialize one.  */
 566
 567 #define OPS_MAGIC       3840
 568
 569 /* The ops structure for our "current" target process.  This should
 570    never be NULL.  If there is no target, it points to the dummy_target.  */
 571
 572 extern struct target_ops current_target;
 573
 574 /* Define easy words for doing these operations on our current target.  */
 575
 576 #define target_shortname        (current_target.to_shortname)
 577 #define target_longname         (current_target.to_longname)
 578
 579 /* Does whatever cleanup is required for a target that we are no
 580    longer going to be calling.  QUITTING indicates that GDB is exiting
 581    and should not get hung on an error (otherwise it is important to
 582    perform clean termination, even if it takes a while).  This routine
 583    is automatically always called when popping the target off the
 584    target stack (to_beneath is undefined).  Closing file descriptors
 585    and freeing all memory allocated memory are typical things it
 586    should do.  */
 587
 588 void target_close (struct target_ops *targ, int quitting);
 589
 590 /* Attaches to a process on the target side.  Arguments are as passed
 591    to the `attach' command by the user.  This routine can be called
 592    when the target is not on the target-stack, if the target_can_run
 593    routine returns 1; in that case, it must push itself onto the stack.
 594    Upon exit, the target should be ready for normal operations, and
 595    should be ready to deliver the status of the process immediately
 596    (without waiting) to an upcoming target_wait call.  */
 597
 598 void target_attach (char *, int);
 599
 600 /* Some targets don't generate traps when attaching to the inferior,
 601    or their target_attach implementation takes care of the waiting.
 602    These targets must set to_attach_no_wait.  */
 603
 604 #define target_attach_no_wait \
 605      (current_target.to_attach_no_wait)
 606
 607 /* The target_attach operation places a process under debugger control,
 608    and stops the process.
 609
 610    This operation provides a target-specific hook that allows the
 611    necessary bookkeeping to be performed after an attach completes.  */
 612 #define target_post_attach(pid) \
 613      (*current_target.to_post_attach) (pid)
 614
 615 /* Takes a program previously attached to and detaches it.
 616    The program may resume execution (some targets do, some don't) and will
 617    no longer stop on signals, etc.  We better not have left any breakpoints
 618    in the program or it'll die when it hits one.  ARGS is arguments
 619    typed by the user (e.g. a signal to send the process).  FROM_TTY
 620    says whether to be verbose or not.  */
 621
 622 extern void target_detach (char *, int);
 623
 624 /* Disconnect from the current target without resuming it (leaving it
 625    waiting for a debugger).  */
 626
 627 extern void target_disconnect (char *, int);
 628
 629 /* Resume execution of the target process PTID.  STEP says whether to
 630    single-step or to run free; SIGGNAL is the signal to be given to
 631    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 632    pass TARGET_SIGNAL_DEFAULT.  */
 633
 634 extern void target_resume (ptid_t ptid, int step, enum target_signal signal);
 635
 636 /* Wait for process pid to do something.  PTID = -1 to wait for any
 637    pid to do something.  Return pid of child, or -1 in case of error;
 638    store status through argument pointer STATUS.  Note that it is
 639    _NOT_ OK to throw_exception() out of target_wait() without popping
 640    the debugging target from the stack; GDB isn't prepared to get back
 641    to the prompt with a debugging target but without the frame cache,
 642    stop_pc, etc., set up.  OPTIONS is a bitwise OR of TARGET_W*
 643    options.  */
 644
 645 extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status,
 646                            int options);
 647
 648 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 649
 650 extern void target_fetch_registers (struct regcache *regcache, int regno);
 651
 652 /* Store at least register REGNO, or all regs if REGNO == -1.
 653    It can store as many registers as it wants to, so target_prepare_to_store
 654    must have been previously called.  Calls error() if there are problems.  */
 655
 656 extern void target_store_registers (struct regcache *regcache, int regs);
 657
 658 /* Get ready to modify the registers array.  On machines which store
 659    individual registers, this doesn't need to do anything.  On machines
 660    which store all the registers in one fell swoop, this makes sure
 661    that REGISTERS contains all the registers from the program being
 662    debugged.  */
 663
 664 #define target_prepare_to_store(regcache)       \
 665      (*current_target.to_prepare_to_store) (regcache)
 666
 667 /* Returns true if this target can debug multiple processes
 668    simultaneously.  */
 669
 670 #define target_supports_multi_process() \
 671      (*current_target.to_supports_multi_process) ()
 672
 673 extern DCACHE *target_dcache;
 674
 675 extern int target_read_string (CORE_ADDR, char **, int, int *);
 676
 677 extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 678
 679 extern int target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 680                                 int len);
 681
 682 /* Fetches the target's memory map.  If one is found it is sorted
 683    and returned, after some consistency checking.  Otherwise, NULL
 684    is returned.  */
 685 VEC(mem_region_s) *target_memory_map (void);
 686
 687 /* Erase the specified flash region.  */
 688 void target_flash_erase (ULONGEST address, LONGEST length);
 689
 690 /* Finish a sequence of flash operations.  */
 691 void target_flash_done (void);
 692
 693 /* Describes a request for a memory write operation.  */
 694 struct memory_write_request
 695   {
 696     /* Begining address that must be written. */
 697     ULONGEST begin;
 698     /* Past-the-end address. */
 699     ULONGEST end;
 700     /* The data to write. */
 701     gdb_byte *data;
 702     /* A callback baton for progress reporting for this request.  */
 703     void *baton;
 704   };
 705 typedef struct memory_write_request memory_write_request_s;
 706 DEF_VEC_O(memory_write_request_s);
 707
 708 /* Enumeration specifying different flash preservation behaviour.  */
 709 enum flash_preserve_mode
 710   {
 711     flash_preserve,
 712     flash_discard
 713   };
 714
 715 /* Write several memory blocks at once.  This version can be more
 716    efficient than making several calls to target_write_memory, in
 717    particular because it can optimize accesses to flash memory.
 718
 719    Moreover, this is currently the only memory access function in gdb
 720    that supports writing to flash memory, and it should be used for
 721    all cases where access to flash memory is desirable.
 722
 723    REQUESTS is the vector (see vec.h) of memory_write_request.
 724    PRESERVE_FLASH_P indicates what to do with blocks which must be
 725      erased, but not completely rewritten.
 726    PROGRESS_CB is a function that will be periodically called to provide
 727      feedback to user.  It will be called with the baton corresponding
 728      to the request currently being written.  It may also be called
 729      with a NULL baton, when preserved flash sectors are being rewritten.
 730
 731    The function returns 0 on success, and error otherwise.  */
 732 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 733                                 enum flash_preserve_mode preserve_flash_p,
 734                                 void (*progress_cb) (ULONGEST, void *));
 735
 736 /* From infrun.c.  */
 737
 738 extern int inferior_has_forked (ptid_t pid, ptid_t *child_pid);
 739
 740 extern int inferior_has_vforked (ptid_t pid, ptid_t *child_pid);
 741
 742 extern int inferior_has_execd (ptid_t pid, char **execd_pathname);
 743
 744 /* Print a line about the current target.  */
 745
 746 #define target_files_info()     \
 747      (*current_target.to_files_info) (&current_target)
 748
 749 /* Insert a breakpoint at address BP_TGT->placed_address in the target
 750    machine.  Result is 0 for success, or an errno value.  */
 751
 752 #define target_insert_breakpoint(gdbarch, bp_tgt)       \
 753      (*current_target.to_insert_breakpoint) (gdbarch, bp_tgt)
 754
 755 /* Remove a breakpoint at address BP_TGT->placed_address in the target
 756    machine.  Result is 0 for success, or an errno value.  */
 757
 758 #define target_remove_breakpoint(gdbarch, bp_tgt)       \
 759      (*current_target.to_remove_breakpoint) (gdbarch, bp_tgt)
 760
 761 /* Initialize the terminal settings we record for the inferior,
 762    before we actually run the inferior.  */
 763
 764 #define target_terminal_init() \
 765      (*current_target.to_terminal_init) ()
 766
 767 /* Put the inferior's terminal settings into effect.
 768    This is preparation for starting or resuming the inferior.  */
 769
 770 extern void target_terminal_inferior (void);
 771
 772 /* Put some of our terminal settings into effect,
 773    enough to get proper results from our output,
 774    but do not change into or out of RAW mode
 775    so that no input is discarded.
 776
 777    After doing this, either terminal_ours or terminal_inferior
 778    should be called to get back to a normal state of affairs.  */
 779
 780 #define target_terminal_ours_for_output() \
 781      (*current_target.to_terminal_ours_for_output) ()
 782
 783 /* Put our terminal settings into effect.
 784    First record the inferior's terminal settings
 785    so they can be restored properly later.  */
 786
 787 #define target_terminal_ours() \
 788      (*current_target.to_terminal_ours) ()
 789
 790 /* Save our terminal settings.
 791    This is called from TUI after entering or leaving the curses
 792    mode.  Since curses modifies our terminal this call is here
 793    to take this change into account.  */
 794
 795 #define target_terminal_save_ours() \
 796      (*current_target.to_terminal_save_ours) ()
 797
 798 /* Print useful information about our terminal status, if such a thing
 799    exists.  */
 800
 801 #define target_terminal_info(arg, from_tty) \
 802      (*current_target.to_terminal_info) (arg, from_tty)
 803
 804 /* Kill the inferior process.   Make it go away.  */
 805
 806 extern void target_kill (void);
 807
 808 /* Load an executable file into the target process.  This is expected
 809    to not only bring new code into the target process, but also to
 810    update GDB's symbol tables to match.
 811
 812    ARG contains command-line arguments, to be broken down with
 813    buildargv ().  The first non-switch argument is the filename to
 814    load, FILE; the second is a number (as parsed by strtoul (..., ...,
 815    0)), which is an offset to apply to the load addresses of FILE's
 816    sections.  The target may define switches, or other non-switch
 817    arguments, as it pleases.  */
 818
 819 extern void target_load (char *arg, int from_tty);
 820
 821 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 822    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 823    symbol should be returned.  The result is 0 if successful, nonzero
 824    if the symbol does not exist in the target environment.  This
 825    function should not call error() if communication with the target
 826    is interrupted, since it is called from symbol reading, but should
 827    return nonzero, possibly doing a complain().  */
 828
 829 #define target_lookup_symbol(name, addrp) \
 830      (*current_target.to_lookup_symbol) (name, addrp)
 831
 832 /* Start an inferior process and set inferior_ptid to its pid.
 833    EXEC_FILE is the file to run.
 834    ALLARGS is a string containing the arguments to the program.
 835    ENV is the environment vector to pass.  Errors reported with error().
 836    On VxWorks and various standalone systems, we ignore exec_file.  */
 837
 838 void target_create_inferior (char *exec_file, char *args,
 839                              char **env, int from_tty);
 840
 841 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 842    notification of inferior events such as fork and vork immediately
 843    after the inferior is created.  (This because of how gdb gets an
 844    inferior created via invoking a shell to do it.  In such a scenario,
 845    if the shell init file has commands in it, the shell will fork and
 846    exec for each of those commands, and we will see each such fork
 847    event.  Very bad.)
 848
 849    Such targets will supply an appropriate definition for this function.  */
 850
 851 #define target_post_startup_inferior(ptid) \
 852      (*current_target.to_post_startup_inferior) (ptid)
 853
 854 /* On some targets, the sequence of starting up an inferior requires
 855    some synchronization between gdb and the new inferior process, PID.  */
 856
 857 #define target_acknowledge_created_inferior(pid) \
 858      (*current_target.to_acknowledge_created_inferior) (pid)
 859
 860 /* On some targets, we can catch an inferior fork or vfork event when
 861    it occurs.  These functions insert/remove an already-created
 862    catchpoint for such events.  */
 863
 864 #define target_insert_fork_catchpoint(pid) \
 865      (*current_target.to_insert_fork_catchpoint) (pid)
 866
 867 #define target_remove_fork_catchpoint(pid) \
 868      (*current_target.to_remove_fork_catchpoint) (pid)
 869
 870 #define target_insert_vfork_catchpoint(pid) \
 871      (*current_target.to_insert_vfork_catchpoint) (pid)
 872
 873 #define target_remove_vfork_catchpoint(pid) \
 874      (*current_target.to_remove_vfork_catchpoint) (pid)
 875
 876 /* If the inferior forks or vforks, this function will be called at
 877    the next resume in order to perform any bookkeeping and fiddling
 878    necessary to continue debugging either the parent or child, as
 879    requested, and releasing the other.  Information about the fork
 880    or vfork event is available via get_last_target_status ().
 881    This function returns 1 if the inferior should not be resumed
 882    (i.e. there is another event pending).  */
 883
 884 int target_follow_fork (int follow_child);
 885
 886 /* On some targets, we can catch an inferior exec event when it
 887    occurs.  These functions insert/remove an already-created
 888    catchpoint for such events.  */
 889
 890 #define target_insert_exec_catchpoint(pid) \
 891      (*current_target.to_insert_exec_catchpoint) (pid)
 892
 893 #define target_remove_exec_catchpoint(pid) \
 894      (*current_target.to_remove_exec_catchpoint) (pid)
 895
 896 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 897    exit code of PID, if any.  */
 898
 899 #define target_has_exited(pid,wait_status,exit_status) \
 900      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 901
 902 /* The debugger has completed a blocking wait() call.  There is now
 903    some process event that must be processed.  This function should
 904    be defined by those targets that require the debugger to perform
 905    cleanup or internal state changes in response to the process event.  */
 906
 907 /* The inferior process has died.  Do what is right.  */
 908
 909 void target_mourn_inferior (void);
 910
 911 /* Does target have enough data to do a run or attach command? */
 912
 913 #define target_can_run(t) \
 914      ((t)->to_can_run) ()
 915
 916 /* post process changes to signal handling in the inferior.  */
 917
 918 #define target_notice_signals(ptid) \
 919      (*current_target.to_notice_signals) (ptid)
 920
 921 /* Check to see if a thread is still alive.  */
 922
 923 extern int target_thread_alive (ptid_t ptid);
 924
 925 /* Query for new threads and add them to the thread list.  */
 926
 927 extern void target_find_new_threads (void);
 928
 929 /* Make target stop in a continuable fashion.  (For instance, under
 930    Unix, this should act like SIGSTOP).  This function is normally
 931    used by GUIs to implement a stop button.  */
 932
 933 #define target_stop(ptid) (*current_target.to_stop) (ptid)
 934
 935 /* Send the specified COMMAND to the target's monitor
 936    (shell,interpreter) for execution.  The result of the query is
 937    placed in OUTBUF.  */
 938
 939 #define target_rcmd(command, outbuf) \
 940      (*current_target.to_rcmd) (command, outbuf)
 941
 942
 943 /* Does the target include all of memory, or only part of it?  This
 944    determines whether we look up the target chain for other parts of
 945    memory if this target can't satisfy a request.  */
 946
 947 extern int target_has_all_memory_1 (void);
 948 #define target_has_all_memory target_has_all_memory_1 ()
 949
 950 /* Does the target include memory?  (Dummy targets don't.)  */
 951
 952 extern int target_has_memory_1 (void);
 953 #define target_has_memory target_has_memory_1 ()
 954
 955 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 956    we start a process.)  */
 957
 958 extern int target_has_stack_1 (void);
 959 #define target_has_stack target_has_stack_1 ()
 960
 961 /* Does the target have registers?  (Exec files don't.)  */
 962
 963 extern int target_has_registers_1 (void);
 964 #define target_has_registers target_has_registers_1 ()
 965
 966 /* Does the target have execution?  Can we make it jump (through
 967    hoops), or pop its stack a few times?  This means that the current
 968    target is currently executing; for some targets, that's the same as
 969    whether or not the target is capable of execution, but there are
 970    also targets which can be current while not executing.  In that
 971    case this will become true after target_create_inferior or
 972    target_attach.  */
 973
 974 extern int target_has_execution_1 (void);
 975 #define target_has_execution target_has_execution_1 ()
 976
 977 /* Default implementations for process_stratum targets.  Return true
 978    if there's a selected inferior, false otherwise.  */
 979
 980 extern int default_child_has_all_memory (struct target_ops *ops);
 981 extern int default_child_has_memory (struct target_ops *ops);
 982 extern int default_child_has_stack (struct target_ops *ops);
 983 extern int default_child_has_registers (struct target_ops *ops);
 984 extern int default_child_has_execution (struct target_ops *ops);
 985
 986 /* Can the target support the debugger control of thread execution?
 987    Can it lock the thread scheduler?  */
 988
 989 #define target_can_lock_scheduler \
 990      (current_target.to_has_thread_control & tc_schedlock)
 991
 992 /* Should the target enable async mode if it is supported?  Temporary
 993    cludge until async mode is a strict superset of sync mode.  */
 994 extern int target_async_permitted;
 995
 996 /* Can the target support asynchronous execution? */
 997 #define target_can_async_p() (current_target.to_can_async_p ())
 998
 999 /* Is the target in asynchronous execution mode? */
1000 #define target_is_async_p() (current_target.to_is_async_p ())
1001
1002 int target_supports_non_stop (void);
1003
1004 /* Put the target in async mode with the specified callback function. */
1005 #define target_async(CALLBACK,CONTEXT) \
1006      (current_target.to_async ((CALLBACK), (CONTEXT)))
1007
1008 /* This is to be used ONLY within call_function_by_hand(). It provides
1009    a workaround, to have inferior function calls done in sychronous
1010    mode, even though the target is asynchronous. After
1011    target_async_mask(0) is called, calls to target_can_async_p() will
1012    return FALSE , so that target_resume() will not try to start the
1013    target asynchronously. After the inferior stops, we IMMEDIATELY
1014    restore the previous nature of the target, by calling
1015    target_async_mask(1). After that, target_can_async_p() will return
1016    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
1017
1018    FIXME ezannoni 1999-12-13: we won't need this once we move
1019    the turning async on and off to the single execution commands,
1020    from where it is done currently, in remote_resume().  */
1021
1022 #define target_async_mask(MASK) \
1023   (current_target.to_async_mask (MASK))
1024
1025 /* Converts a process id to a string.  Usually, the string just contains
1026    `process xyz', but on some systems it may contain
1027    `process xyz thread abc'.  */
1028
1029 extern char *target_pid_to_str (ptid_t ptid);
1030
1031 extern char *normal_pid_to_str (ptid_t ptid);
1032
1033 /* Return a short string describing extra information about PID,
1034    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1035    is okay.  */
1036
1037 #define target_extra_thread_info(TP) \
1038      (current_target.to_extra_thread_info (TP))
1039
1040 /* Attempts to find the pathname of the executable file
1041    that was run to create a specified process.
1042
1043    The process PID must be stopped when this operation is used.
1044
1045    If the executable file cannot be determined, NULL is returned.
1046
1047    Else, a pointer to a character string containing the pathname
1048    is returned.  This string should be copied into a buffer by
1049    the client if the string will not be immediately used, or if
1050    it must persist.  */
1051
1052 #define target_pid_to_exec_file(pid) \
1053      (current_target.to_pid_to_exec_file) (pid)
1054
1055 /* See the to_thread_architecture description in struct target_ops.  */
1056
1057 #define target_thread_architecture(ptid) \
1058      (current_target.to_thread_architecture (&current_target, ptid))
1059
1060 /*
1061  * Iterator function for target memory regions.
1062  * Calls a callback function once for each memory region 'mapped'
1063  * in the child process.  Defined as a simple macro rather than
1064  * as a function macro so that it can be tested for nullity.
1065  */
1066
1067 #define target_find_memory_regions(FUNC, DATA) \
1068      (current_target.to_find_memory_regions) (FUNC, DATA)
1069
1070 /*
1071  * Compose corefile .note section.
1072  */
1073
1074 #define target_make_corefile_notes(BFD, SIZE_P) \
1075      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
1076
1077 /* Hardware watchpoint interfaces.  */
1078
1079 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1080    write).  */
1081
1082 #define target_stopped_by_watchpoint \
1083    (*current_target.to_stopped_by_watchpoint)
1084
1085 /* Non-zero if we have steppable watchpoints  */
1086
1087 #define target_have_steppable_watchpoint \
1088    (current_target.to_have_steppable_watchpoint)
1089
1090 /* Non-zero if we have continuable watchpoints  */
1091
1092 #define target_have_continuable_watchpoint \
1093    (current_target.to_have_continuable_watchpoint)
1094
1095 /* Provide defaults for hardware watchpoint functions.  */
1096
1097 /* If the *_hw_beakpoint functions have not been defined
1098    elsewhere use the definitions in the target vector.  */
1099
1100 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1101    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1102    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1103    (including this one?).  OTHERTYPE is who knows what...  */
1104
1105 #define target_can_use_hardware_watchpoint(TYPE,CNT,OTHERTYPE) \
1106  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1107
1108 #define target_region_ok_for_hw_watchpoint(addr, len) \
1109     (*current_target.to_region_ok_for_hw_watchpoint) (addr, len)
1110
1111
1112 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1113    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1114    success, non-zero for failure.  */
1115
1116 #define target_insert_watchpoint(addr, len, type)       \
1117      (*current_target.to_insert_watchpoint) (addr, len, type)
1118
1119 #define target_remove_watchpoint(addr, len, type)       \
1120      (*current_target.to_remove_watchpoint) (addr, len, type)
1121
1122 #define target_insert_hw_breakpoint(gdbarch, bp_tgt) \
1123      (*current_target.to_insert_hw_breakpoint) (gdbarch, bp_tgt)
1124
1125 #define target_remove_hw_breakpoint(gdbarch, bp_tgt) \
1126      (*current_target.to_remove_hw_breakpoint) (gdbarch, bp_tgt)
1127
1128 #define target_stopped_data_address(target, x) \
1129     (*target.to_stopped_data_address) (target, x)
1130
1131 #define target_watchpoint_addr_within_range(target, addr, start, length) \
1132   (*target.to_watchpoint_addr_within_range) (target, addr, start, length)
1133
1134 /* Target can execute in reverse?  */
1135 #define target_can_execute_reverse \
1136      (current_target.to_can_execute_reverse ? \
1137       current_target.to_can_execute_reverse () : 0)
1138
1139 extern const struct target_desc *target_read_description (struct target_ops *);
1140
1141 #define target_get_ada_task_ptid(lwp, tid) \
1142      (*current_target.to_get_ada_task_ptid) (lwp,tid)
1143
1144 /* Utility implementation of searching memory.  */
1145 extern int simple_search_memory (struct target_ops* ops,
1146                                  CORE_ADDR start_addr,
1147                                  ULONGEST search_space_len,
1148                                  const gdb_byte *pattern,
1149                                  ULONGEST pattern_len,
1150                                  CORE_ADDR *found_addrp);
1151
1152 /* Main entry point for searching memory.  */
1153 extern int target_search_memory (CORE_ADDR start_addr,
1154                                  ULONGEST search_space_len,
1155                                  const gdb_byte *pattern,
1156                                  ULONGEST pattern_len,
1157                                  CORE_ADDR *found_addrp);
1158
1159 /* Command logging facility.  */
1160
1161 #define target_log_command(p)                                           \
1162   do                                                                    \
1163     if (current_target.to_log_command)                                  \
1164       (*current_target.to_log_command) (p);                             \
1165   while (0)
1166
1167 /* Routines for maintenance of the target structures...
1168
1169    add_target:   Add a target to the list of all possible targets.
1170
1171    push_target:  Make this target the top of the stack of currently used
1172    targets, within its particular stratum of the stack.  Result
1173    is 0 if now atop the stack, nonzero if not on top (maybe
1174    should warn user).
1175
1176    unpush_target: Remove this from the stack of currently used targets,
1177    no matter where it is on the list.  Returns 0 if no
1178    change, 1 if removed from stack.
1179
1180    pop_target:   Remove the top thing on the stack of current targets.  */
1181
1182 extern void add_target (struct target_ops *);
1183
1184 extern int push_target (struct target_ops *);
1185
1186 extern int unpush_target (struct target_ops *);
1187
1188 extern void target_pre_inferior (int);
1189
1190 extern void target_preopen (int);
1191
1192 extern void pop_target (void);
1193
1194 /* Does whatever cleanup is required to get rid of all pushed targets.
1195    QUITTING is propagated to target_close; it indicates that GDB is
1196    exiting and should not get hung on an error (otherwise it is
1197    important to perform clean termination, even if it takes a
1198    while).  */
1199 extern void pop_all_targets (int quitting);
1200
1201 /* Like pop_all_targets, but pops only targets whose stratum is
1202    strictly above ABOVE_STRATUM.  */
1203 extern void pop_all_targets_above (enum strata above_stratum, int quitting);
1204
1205 extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
1206                                                CORE_ADDR offset);
1207
1208 /* Struct target_section maps address ranges to file sections.  It is
1209    mostly used with BFD files, but can be used without (e.g. for handling
1210    raw disks, or files not in formats handled by BFD).  */
1211
1212 struct target_section
1213   {
1214     CORE_ADDR addr;             /* Lowest address in section */
1215     CORE_ADDR endaddr;          /* 1+highest address in section */
1216
1217     struct bfd_section *the_bfd_section;
1218
1219     bfd *bfd;                   /* BFD file pointer */
1220   };
1221
1222 /* Holds an array of target sections.  Defined by [SECTIONS..SECTIONS_END[.  */
1223
1224 struct target_section_table
1225 {
1226   struct target_section *sections;
1227   struct target_section *sections_end;
1228 };
1229
1230 /* Return the "section" containing the specified address.  */
1231 struct target_section *target_section_by_addr (struct target_ops *target,
1232                                                CORE_ADDR addr);
1233
1234 /* Return the target section table this target (or the targets
1235    beneath) currently manipulate.  */
1236
1237 extern struct target_section_table *target_get_section_table
1238   (struct target_ops *target);
1239
1240 /* From mem-break.c */
1241
1242 extern int memory_remove_breakpoint (struct gdbarch *, struct bp_target_info *);
1243
1244 extern int memory_insert_breakpoint (struct gdbarch *, struct bp_target_info *);
1245
1246 extern int default_memory_remove_breakpoint (struct gdbarch *, struct bp_target_info *);
1247
1248 extern int default_memory_insert_breakpoint (struct gdbarch *, struct bp_target_info *);
1249
1250
1251 /* From target.c */
1252
1253 extern void initialize_targets (void);
1254
1255 extern NORETURN void noprocess (void) ATTR_NORETURN;
1256
1257 extern void target_require_runnable (void);
1258
1259 extern void find_default_attach (struct target_ops *, char *, int);
1260
1261 extern void find_default_create_inferior (struct target_ops *,
1262                                           char *, char *, char **, int);
1263
1264 extern struct target_ops *find_run_target (void);
1265
1266 extern struct target_ops *find_core_target (void);
1267
1268 extern struct target_ops *find_target_beneath (struct target_ops *);
1269
1270 /* Read OS data object of type TYPE from the target, and return it in
1271    XML format.  The result is NUL-terminated and returned as a string,
1272    allocated using xmalloc.  If an error occurs or the transfer is
1273    unsupported, NULL is returned.  Empty objects are returned as
1274    allocated but empty strings.  */
1275
1276 extern char *target_get_osdata (const char *type);
1277
1278 \f
1279 /* Stuff that should be shared among the various remote targets.  */
1280
1281 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1282    information (higher values, more information).  */
1283 extern int remote_debug;
1284
1285 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1286 extern int baud_rate;
1287 /* Timeout limit for response from target. */
1288 extern int remote_timeout;
1289
1290 \f
1291 /* Functions for helping to write a native target.  */
1292
1293 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1294 extern void store_waitstatus (struct target_waitstatus *, int);
1295
1296 /* These are in common/signals.c, but they're only used by gdb.  */
1297 extern enum target_signal default_target_signal_from_host (struct gdbarch *,
1298                                                            int);
1299 extern int default_target_signal_to_host (struct gdbarch *,
1300                                           enum target_signal);
1301
1302 /* Convert from a number used in a GDB command to an enum target_signal.  */
1303 extern enum target_signal target_signal_from_command (int);
1304 /* End of files in common/signals.c.  */
1305
1306 /* Set the show memory breakpoints mode to show, and installs a cleanup
1307    to restore it back to the current value.  */
1308 extern struct cleanup *make_show_memory_breakpoints_cleanup (int show);
1309
1310 \f
1311 /* Imported from machine dependent code */
1312
1313 /* Blank target vector entries are initialized to target_ignore. */
1314 void target_ignore (void);
1315
1316 extern struct target_ops deprecated_child_ops;
1317
1318 #endif /* !defined (TARGET_H) */